This proposal requests funds for the purchase of a Nikon N-SIM/N-STORM Super-Resolution Microscope System. The instrument combines both SIM and STORM systems into one platform. The N-SIM (Structured Illumination Microscopy) achieves a resolution two times higher than that of conventional confocal microscopes in each dimension. It is equipped with 5 laser lines (458/488/515/532/561 nm) and capable of 3D imaging up to 20 m thickness. The N-STORM (Stochastic Optical Reconstruction Microscopy) is a single-molecule localization-based microscope that generates a dramatically enhanced resolution that is ten times (approx. 20 nm laterally) higher than confocal microscopy in all three axes. The N-STORM comes equipped with a 4-laser illumination unit (405/488/561/647 nm) and 3D STORM capability. Currently, there is no super-resolution microscope available at Stony Brook University. The system will facilitate the spatial resolution of protein localization and cellular structures beyond the diffraction limit of ~200nm, enabling investigators to explore fundamental biological problems related to human disease at high precision. Management and operation of the system will be provided by a technical specialist, who will also assists users in developing staining and imaging protocols for special projects, as well as helping investigators in the analysis of super-resolution data. )